Seasonal and gender impacts on fecal exposure trends in an urban slum

Abstract

Seasonal and gender impacts have not been well considered in fecal exposure assessment, especially in low- and middle-income countries. This study examined the seasonal and gender impacts on fecal exposure trends in children through daily living activities in an urban slum in Bangladesh. We determined Escherichia coli concentrations in seven types of environmental samples (n = 232) and the activity data of children via diary recording, questionnaires, and interview surveys. Daily and monthly exposures were stochastically estimated for drinking, eating, pond bathing, well bathing, and hand-to-mouth contact. Of the five pathways, pond bathing and drinking contributed a large part of the daily and monthly exposure. Significant seasonal differences were observed in daily exposures for bathing, which were higher in the rainy season (2.59 × 102 CFU/day for boys and 6.19 × 10−1 CFU/day for girls) than in the dry season (1.69 × 102; 4.30 × 10−2), because of longer pond bathing time and more contaminated bathing water in the rainy season. In contrast, eating had significantly higher exposure in the dry season (3.71 × 10; 3.22 × 10) than the rainy season (1.50 × 10; 1.24 × 10) due to the higher dish contamination. Significantly higher daily exposure was observed in the bathing for boys than girls, as boys spent longer time for bathing at a heavily contaminated pond. HIGHLIGHTS Seasonal and gender impacts on fecal exposure were studied in a slum in Bangladesh.; Escherichia coli levels of seven types of samples and activity data of children were collected.; Fecal exposure of children through five pathways was modeled by seasons and gender.; Drinking predominantly contributed to the exposure of girls regardless of seasons.; Boys’ preference to pond bathing caused the largest exposure in the rainy season.;

Keywords

• children
• environmental media
• escherichia coli
• fecal exposure assessment
• quantitative microbial risk assessment (qmra)